Method to produce a urea ammonium sulphate-based composition

A method for producing a urea ammonium sulphate-based composition in a pipe reactor comprising a first and a second mixing zone, the method comprising the steps of:

• a) directing a liquid stream comprising ammonium bisulphate to the first mixing zone of the pipe reactor;
• b) directing a first stream of ammonia to the first mixing zone of the pipe reactor for reacting with the liquid stream comprising ammonium bisulphate, provided in step a), to obtain a liquid stream comprising ammonium sulphate;
• c) directing the liquid stream comprising ammonium sulphate, provided in step b), to the second mixing zone of the pipe reactor;
• and
• d) directing a liquid stream of urea to the second mixing zone of the pipe reactor for mixing with the liquid stream comprising ammonium sulphate, provided in step b), to obtain a urea ammonium sulphate-based composition;
• wherein in step b), the first stream of ammonia is preheated to a temperature of at least 100° C. prior to being directed to the first mixing zone of the pipe reactor.